Mitochondrial redox adaptations enable alternative aspartate synthesis in SDH-deficient cells

  1. Madeleine L Hart
  2. Evan Quon
  3. Anna-Lena BG Vigil
  4. Ian A Engstrom
  5. Oliver J Newsom
  6. Kristian Davidsen
  7. Pia Hoellerbauer
  8. Samantha M Carlisle
  9. Lucas B Sullivan  Is a corresponding author
  1. Fred Hutchinson Cancer Research Center, United States
  2. New Mexico State University, United States

Abstract

The oxidative tricarboxylic acid (TCA) cycle is a central mitochondrial pathway integrating catabolic conversions of NAD+ to NADH and anabolic production of aspartate, a key amino acid for cell proliferation. Several TCA cycle components are implicated in tumorigenesis, including loss of function mutations in subunits of succinate dehydrogenase (SDH), also known as complex II of the electron transport chain (ETC), but mechanistic understanding of how proliferating cells tolerate the metabolic defects of SDH loss is still lacking. Here, we identify that SDH supports human cell proliferation through aspartate synthesis but, unlike other ETC impairments, the effects of SDH inhibition are not ameliorated by electron acceptor supplementation. Interestingly, we find aspartate production and cell proliferation are restored to SDH-impaired cells by concomitant inhibition of ETC complex I (CI). We determine that the benefits of CI inhibition in this context depend on decreasing mitochondrial NAD+/NADH, which drives SDH-independent aspartate production through pyruvate carboxylation and reductive carboxylation of glutamine. We also find that genetic loss or restoration of SDH selects for cells with concordant CI activity, establishing distinct modalities of mitochondrial metabolism for maintaining aspartate synthesis. These data therefore identify a metabolically beneficial mechanism for CI loss in proliferating cells and reveal how compartmentalized redox changes can impact cellular fitness.

Data availability

All data generated or analyzed during this study are included in the manuscript and supporting files; Source Data files have been provided for Figures 1-8.

Article and author information

Author details

  1. Madeleine L Hart

    Human Biology Division, Fred Hutchinson Cancer Research Center, Seattle, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Evan Quon

    Human Biology Division, Fred Hutchinson Cancer Research Center, Seattle, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Anna-Lena BG Vigil

    Human Biology Division, Fred Hutchinson Cancer Research Center, Seattle, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Ian A Engstrom

    Human Biology Division, Fred Hutchinson Cancer Research Center, Seattle, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Oliver J Newsom

    Human Biology Division, Fred Hutchinson Cancer Research Center, Seattle, United States
    Competing interests
    The authors declare that no competing interests exist.
  6. Kristian Davidsen

    Human Biology Division, Fred Hutchinson Cancer Research Center, Seattle, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-3821-6902
  7. Pia Hoellerbauer

    Human Biology Division, Fred Hutchinson Cancer Research Center, Seattle, United States
    Competing interests
    The authors declare that no competing interests exist.
  8. Samantha M Carlisle

    Department of Chemistry and Biochemistry, New Mexico State University, Las Cruces, United States
    Competing interests
    The authors declare that no competing interests exist.
  9. Lucas B Sullivan

    Human Biology Division, Fred Hutchinson Cancer Research Center, Seattle, United States
    For correspondence
    lucas@fredhutch.org
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-6745-8222

Funding

National Cancer Institute (P30CA015704)

  • Lucas B Sullivan

National Institute of General Medical Sciences (T32GM095421)

  • Madeleine L Hart

National Cancer Institute (R00CA218679-03S1)

  • Madeleine L Hart

National Cancer Institute (R00CA218679)

  • Lucas B Sullivan

National Institute of General Medical Sciences (R35GM147118)

  • Lucas B Sullivan

Andy Hill Cancer Research Endowment (CARE Award)

  • Lucas B Sullivan

National Cancer Institute (U54CA132381)

  • Samantha M Carlisle
  • Lucas B Sullivan

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Mark S Sharpley, Cedars-Sinai Medical Center, United States

Ethics

Animal experimentation: All mouse work was performed in accordance with FHCC-approved IACUC protocol 51069 and AAALAS guidelines and ethical regulations.

Version history

  1. Preprint posted: March 14, 2022 (view preprint)
  2. Received: March 15, 2022
  3. Accepted: March 6, 2023
  4. Accepted Manuscript published: March 8, 2023 (version 1)
  5. Accepted Manuscript updated: March 9, 2023 (version 2)
  6. Version of Record published: March 20, 2023 (version 3)

Copyright

© 2023, Hart et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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  1. Madeleine L Hart
  2. Evan Quon
  3. Anna-Lena BG Vigil
  4. Ian A Engstrom
  5. Oliver J Newsom
  6. Kristian Davidsen
  7. Pia Hoellerbauer
  8. Samantha M Carlisle
  9. Lucas B Sullivan
(2023)
Mitochondrial redox adaptations enable alternative aspartate synthesis in SDH-deficient cells
eLife 12:e78654.
https://doi.org/10.7554/eLife.78654

Share this article

https://doi.org/10.7554/eLife.78654

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